The present invention addresses an improvement over the drive release brake assembly described in Brazilian Patent Application Ser. No. PI 8001127, filed Feb. 26, 1980 by the same inventor herein and which is now published.
The present invention generally refers to mechanical drive release brake assemblies to control relative rotation between rotary members. More particularly, it refers to those drive assemblies employed in hoists or similar things which require a type of automatic brake which prevents accidental release.
Hoists have numerous uses in elevators, winches and similar things. They can be mechanically or electrically driven and can be used jointly with a pulley, spool or cube to capture and thread line or with a winch to merely recapture line. In many uses, it is desirable that the drive assembly used in a hoist control be easy to operate, trustworthy, and durable. Besides this, it is desirable, and at times imperative, that the drive assembly have an automatic locking characteristic in order to prevent accidental release or discharge of the hoist line in case of motor failure.
Consequently, it is an object of the invention to provide a hoist which is sturdy and trustworthy, while not necessarily complicated or difficult to operate and maintain.
Another object of the invention is to provide a drive release brake assembly which can be used in a hoist with backward and forward motion, but which automatically locks against those motions in case of motor failure.
Yet another object of the invention is to provide a drive release brake assembly which is useful in combination with a line-threading pulley, winch or similar device.